C#图像处理之图像均值方差计算的方法

本文实例讲述了c#图像处理之图像均值方差计算的方法。分享给大家供大家参考。具体如下：

//本函数均是基于rgb颜色空间计算
//定义图像均值函数（rgb空间）
public double anbitmap(bitmap a)
{
  double v = 0;
  rectangle rect = new rectangle(0, 0, a.width, a.height);
  system.drawing.imaging.bitmapdata bmpdata = a.lockbits(rect, system.drawing.imaging.imagelockmode.readwrite, system.drawing.imaging.pixelformat.format24bpprgb);
  unsafe
  {
   byte* pin = (byte*)bmpdata.scan0.topointer();
   byte* p;
   int r, g, b;
   double meanvalue = 0, sum = 0; 
   int stride = bmpdata.stride;
   for (int y = 0; y < a.height; y++)
   {
     for (int x = 0; x < a.width; x++)
     {
     p = pin;
     b = p[0];
     g = p[1];
     r = p[2];
     sum += b * 0.114 + g * 0.587 + r * 0.299;
     pin += 3;
     }
     pin += stride - a.width * 3;
   }
   meanvalue = sum / (a.width * a.height);
   v = meanvalue;
  }
  a.unlockbits(bmpdata);
  return v;  //返回图像均值v
}
//定义图像统计方差函数（rgb空间）
public double anconbitmap(bitmap a,double meanvalue)
{
  double v = 0;
  rectangle rect = new rectangle(0, 0, a.width, a.height);
  system.drawing.imaging.bitmapdata bmpdata = a.lockbits(rect, system.drawing.imaging.imagelockmode.readwrite, system.drawing.imaging.pixelformat.format24bpprgb);
  unsafe
  {
   byte* pin = (byte*)bmpdata.scan0.topointer();
   byte* p;
   int r, g, b;
   double conv = 0, sum = 0;
   int stride = bmpdata.stride;
   for (int y = 0; y < a.height; y++)
   {
     for (int x = 0; x < a.width; x++)
     {
     p = pin;
     b = p[0];
     g = p[1];
     r = p[2];
     sum += (b * 0.114 + g * 0.587 + r * 0.299 - meanvalue) * (b * 0.114 + g * 0.587 + r * 0.299 - meanvalue);
     pin += 3;
     }
     pin += stride - a.width * 3;
    }
    conv = sum / (a.width * a.height-1);
   v = conv;
  }
  a.unlockbits(bmpdata);
  return v;  //返回图像方差v
}

希望本文所述对大家的c#程序设计有所帮助。